Well, you probably do want to get a rifle with an anti-Borg bonus if you plan on doing any STFs. As for other weapons, you want to have a Pulsewave of some sort for heavy damage up close, a Sniper rifle for single-target damage (i.e. for when you do NOT want to draw aggro from other enemies by hitting them with splash damage), and some type of weapon with a cone-shaped AOE secondary fire (Full Auto rifle, Minigun, Split Beam, or whatever--but beware that Borg adapt faster to multi-shot weapons such as Full Auto, Minigun, or Dual Pistols because adaptation counts by number of shots). Also, beware that the secondary-fire range for Wide Beam pistols and Pulsewave rifles is only 15 meters, so if you hit multiple targets with one you will attract counter-attacks from them.

As for what enhancements you might want, the (Dmg) enhancement gives very little damage increase, and the (DoT) enhancement is not too useful against anything with less than 1k hit points because under the Season 4 ground combat system, weaker enemies will die before the damage-over-time has time to do much damage. IMO, the most useful enhancements are any kind of knockback, and (CritD) and (CritH).